Hi @BillyBudd -
Yup, as long as what you put in doesn’t interfere with the o-rings, you should be all set to add something to keep the batteries from bouncing around!
Thanks Matt - sounds like a great idea
- Would the safety fuse be installed in the SSR or somewhere else and do you have any recommendations for the type of fuse?
That’s a super-slick solution! My only reservations would be the bespoke nature of this solution vs. just using standard SSR package (widely available) and simple mount plate with stand-offs. I’m also favouring replacing battery from the front rather than the rear. Discourages people from pulling on the cables to open the end up. But you could add an XT90M-XT90F extension to facilitate that I guess… I’m imagining it would cost more too.
Have some photos to share? Parts list and where to get? Thanks!
Looks good. Installed in the battery enclosure? Where to get and can the battery be shut off w/o opening the endcap?
Oh, I see the the product link now. Looks good and will buy it. I would think BR would put it on their website as a suggested fix.
Just a follow-on thought having been in conversation with Matt @BayDynamics : This solutions gets way more interesting if it could cut output power when voltage gets too low. We recently forgot to turn off a BlueROV and nearly (or possibly have) destroyed a battery. That kind of value-added would move me from an off-the-shelf SSR to a bespoke design.
Agreed @PeterM !
The issue is that a BMS that can cut off the output voltage needs FETS rated to handle the max current that can flow through them. As the system is capable of discharging at well over 100 amps, this is a difficult circuit to design / parts to select!
A “smart battery” that will make issues like you have faced (along with many many others) a thing of the past is on the Blue Robotics roadmap, and planned for development.
Hi Team
So we have been making remote on/off switches for the BlueROV now since 2020. They have been through a few versions since then. Below is a recent one we made for a customer.
Almost every BlueROV in New Zealand has our remote on/off switch upgrade installed. We even made a handful of them with the on/off switch on the topside box instead of on the ROV. They work really well. No one likes having to take the battery out to turn the units off. All our components fit in the battery housing with the battery.
We recently did a prototype with a voltage cut off, where it senses the battery voltage and if its below 9v for more than 10s the battery is cut out. This is purely to stop the battery destroying itself. The voltage sense only needs a few small components to work with our SSR. No big FETS needed at all. We can make adjustments to the voltage level and the user can bypass this feature if they choose with a switch, because there are applications where you 100% dont want the ROV cutting out by itself, so the user can choose when to have the cut out option active.
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Very cool Matt! Do you sell those in a web store or are they custom order? If you’re interested in getting those on the Blue Robotics Reef, please shoot me an email and we can discuss…
I’ve tested/used these for about a year now but am not super in love with the design…
Your unit is obviously a bit longer, but should still work with the standard length battery enclosure? The XT90 whip seems a bit long, is it a pain to cram in when packing in a battery?
Thanks for sharing!
Hi Everyone
If anyone is interested in a Battery On / Off Module for their BlueROV, please let us know. We would be happy to assist anyone who wants one.
Cheers
So far mine is working OK.
The item is out of stock of the website and the website is not repsonding to emails. Are there any good alternatives that somone can suggest?
Well this is nothing fancy or with PMS. But I´m still happy with it, it works for me. I have been using it with standard BR2. Now I´m upgrading my ROV to Heavy with Ping360. So lets see, I think it will still do its job as relay can handle upp to 100A.
I’m working on a series of smart batteries for BlueROV and also general subsea use that will have a rotary switch for controlling power along with undervoltage, overcurrent and many other forms of cutoff protection. Please let me know if you have any requests, concerns, thoughts, etc!
Hi, anyone worked with this switch: Switch Installation ?
Does it work well as an on/off switch for the BlueROV2? Any difficulty?
Hi yes, This switch is good, have had no problem with it. Worked good with standard BR-ROV.
As that said I have upgraded my ROV to Heavy and have Ping360 and it has still worked well with the 100A relay switch board.
Since after the upgrade, I dont have much dive time, only used in a pool and test tank.
Hi @NordinZ -
To clarify - that switch CANNOT. be used to directly switch power from the battery to the BlueROV2, as it has a maximum current capacity of 5 amps. The ROV can draw well over 60 amps in use!
It is a good switch to trigger other, internal circuitry to switch on and off the vehicle, as this product does - that way no high current actually flows thru the Blue Robotics switch.
@diveexplorer - maybe you are using the switch in this way with your 100A relay?
Yes, of course, with a 100A relay.
I thought it would be so clear in this thread that this switch alone can NOT turn the ROV on & OFF. I hope @NordinZ understand that.
Here is my schematic of the switch, connected to the relay and battery.
Thanks @diveexplorer .. I’m a complete nube in hardware matters. The diagram helps, will discuss with my team on its implementation. Do you have a bit more details on the 100A relay; what product would you recommend?


